Indian Railways — complaint against refund of ticket

Address:

500009

Sir, my name is siva, I BOOKED 4 TICKET OF 3AC BY TRAIN 12727 BY PAYING RS 2360 through credit card FOR 3 AUG 2017 BY PNR NO [protected] FROM visakhapatnam to secunderabad.due to some problems i went to visakhapatnam station for cancellation of two tickets. but in counter they said that due to GST some swiping machines was introduced so cancellation cannot be done here. so they said that ticket was made through CV in secunderabad so it will be cancelled in secunderabad. then i asked how can be it done after complition of travelling, then they said that we will give it i eturn on back of the ticket with stamp by showing it will be done. now secunderabad railway nilayam persons are telling that after travelling it cannot be done, they said tht vizag station persons are bluffed me. now i'm puzzled. how can railway persons can do this type of bluffing to passengers pls consider my complaint and help me.